Thermal analysis and experimental verification of the transmission in a lunar drilling system

•This paper focuses on the temperature field of the transmission part in a lunar drilling system.•FEM and TNM models are used to predict the temperature field of the transmission part.•A vacuum test platform is established to measure the temperature rise in different working modes.•The effects of the rotating speed, system load and ambient temperature on the temperature rise are analysed.•Research on the temperature field and heat transfer path can help control the working strategy A planetary gear reducer is used as the transmission in the main driving assembly of a lunar drilling system. The extreme temperature and vacuum environment on the moon can easily cause a large temperature increase of the transmission in the working environment. This effect can cause lubrication failure and a decrease in gear strength, as well as other problems. Based on the thermal network method (TNM) and finite element method (FEM), the temperature field of the transmission under various working environments is predicted. A vacuum test platform is built and an experimental verification method (EVM) is applied to measure the surface temperature of the transmission. Through comparative analysis, the accuracy of the theoretical method and overall heat transfer path are determined. The temperature rise exhibited a linear relationship with the rotating speed and the square root of the system load. Through theoretical analysis and experimental verification, the sampling task can be controlled by predicting the temperature.